Bottom hole choke



June 27, i933.

H. C. OTIS BOTTOM HOLE CHOKE Filed D96. 27, 1952 2 Sheets-Sheet 2 my v Patented .lune 27, 1933 um? stares PATENT ortica HERBERT C. OTIS, OF SHREVEPORT, LOUISIANA BOTTOM HOLE CHOKE Application led December 27, 1932. Serial No. 649,066.

This invention relates to a bottom hole .choke for use in oil wells, and more particularly to a device for use in producing flow in oil wells in which the quantity of gas normally produced with the oil is insuicient to maintain a continuous liow of oil from the well at the desired rate of oil production, even though the most eflicient possible use of the gas is accomplished by means of bottom hole chokes.

It often happens in such wells that a conl siderable amount of gas, called casing-head gas, is stored under pressure in the space between the casing and tubing above the well fluid level. If the fluid level is some distance above the tubing inlet, it is probable that unless some special means are provided, use

cannot be made of the casing-head gas to as sist in raising`the oil through the tubing. since the accumulation of oil around the lower portion of the tubing acts as a fluid seal preventing the gas from entering the base of the tubing. To permit use of this casin gshead gasrsmalleforatnsfcailedets are sometimes made atintervalsinthellllng string;` 'these perforations admitting a.- portion of the gas into the tubingstrinf.;` to assist in/'flo'win'g"`th" `l2""'When it is desired Vto bring thiswgas Yintwthe tubing string at a point,.beneathuthewtluiddevel;use has been made of an additional partial string of small diameter tubing which is clamped-'to the larger string of tubing and extends from its point of entry into the larger tubing to a point above the fluid level of the well, thus permit-ting the casing head gas, if under sufficient pressure, to pass to the interior of the larger tubing.

Neither of these methods permits of ready adjustment of the control rate of entry into the tubing of relative amounts of oil and gas. It is necessary, in order to increase or decrease the area of the openings through which the fluid or gas enters the tubing, to pull and re-run the tubing.

An important object of this invention is the provision of an apparatus for use under such circumstances which will permit the ready change of the diameter of either the gas inlet port or of the oil inlet port.

A further, and more'specitic object of the invention is the provision of a readily pullable choke which is so constructed that it carries removable and interchangeable orificed beans controlling the rate of ow of both the gas and oil.

A further object of the invention is the provision of a construction such that entry of oil may be terminated at any time while the supply of gas is continued, with the result that the tubing may be virtually emptied of fluid following any flowing operation.

These and other objects I attain by the construction shown in the accompanying draw ings wherein, for the purpose of illustration, I have shown a preferred embodiment of my invention and wherein:

Fig. l is a vertical sectional view showing apparatus constructed in accordance with my invention installed in a well;

Fig. 2 is an enlarged detail sectional view through the nipple and choke constructed in accordance with my invention;

Fig. 3 is an elevation of the tool employed when unseating the valve;

Fig. fl is a section on line 4.-4 of Fig. 2;

Fig. 5 is a section on line 55 of Fig. 2;

Fig. 6 is a section on line 6 6 of Fig. 2;

Fig. 7 is a vertical sectional view showing the1 blade section of the choke in elevation; an

Fig. 8 is a fragmentary sectional View through a slightly modified form of choke.

Referring now more particularly to the drawings, the numeral 10 generally designates the casing of a well, and l1 the tubing thereof having an outlet valve 12 at its upper end.

In accordance with my invention, the tubing is provided at a suitable point adjacent its lower end with a locating device in the form of a specially constructed nipple 13 having intermediate its ends a port 14 communicating with an integral L fitting 15 adapted to receive the lower end of a gas admission tube 16 equipped with a downwardly-opening check valve 16--a. This gas admission tube, as shown in Fig. l, may extend above the normal fluid level in th well which is indicated at 17. The bore of the nfpple has upper and lower sections B and B which are of slightly diferent diameter, the upper section B being the larger, and intermediate these sections has a section of still more increased diameter indicated at 18. The increase in diameter at 18 forms upwardly and downwardly facing shoulders 19 and 20. The downwardly facing shoulder is abrupt, and preferably somewhat undercut, while the upwardly facing should-er 19 should be slightly beveled so that packing elements may be run thereby without damage, this being necessary, as will hereinafter become obvious.

Vithin this nipple I employ a choke 21 which is formed in upper and lower sections 22 and 23, each having an axial bor'e therethrough. Near the lower end of the upper section 22 this section is externally reduced to provide an annular recess 24 housing a plurality of locking blades 25. The lower ends of the locking blades are normally coniined by a sleeve 26 secured to the lower end of the section 22 and projecting slightly above the lower end of the annular chamber 24. Sleeve26. is` securedbymeans, offrangi Vble-elementsw 27 and blades 25 have springs 2S co-acting therewith at a point slightly above the upper end of the sleeve so that the upper endsof the blades are urged outwardly. The blades are held against vertical or circumferential movement by means of locking lugs 29 and each blade has upon its outer face an upwardly facing shoulder 30 adapted to engage beneath sleeve 26 under circumstances presently to be described. Above the blades, section 22 is equipped with upwardly and downwardly-facing packings 31 and 32.

The lowr section 23 is, at its upper end, made of slightly less diameter than the interior diameter of the nipple and is equipped with a port connecting its interior and eX- terior, which port comprises an orifice 3 3 formed-in a'removableplug. 34, removal and replacement of which will provide for a change ofpriicesize. At its lower end, the bore of` section 23''is closed by an oriced bean, the lower end of the orifice of this bean being formed as a valve seat for coaction with a valve 36 having a stem 37 extending upwardly through the orifice of the bean and projecting above the upper end of the bean. Valve 36 is spring-seated and guided within an extension 38 of the bean, which extension is pierced at 39 for the flow of fluid.

When the choke is lowered into place in the tubing, the springs 28 will force the blades 25 outwardly so that they will catch beneath the shoulders 20 and prevent upward displacement of the choke. Downward movement of the choke is prevented by opposition of sleeve 26 to the shoulder 19. Vhen the choke is in position in the nipple,

the orifice 33 will be placed in communication with the gas inlet port 14, the down wardly-facing packer 32 of the upper section and the upwardly facing packer 40 of the lowei section sealing against escape of l@ gas pressure except through this orifice. TheN valve 3G isnunseatedm by insertingjhloughthe V'lilflibsprefeiallilly. attached to the lower end.` of a weight 42 havino guides43for guidw.

QQaQt-iQn withtlieiiallsiblfltlheftubing. The actuating stem 41 engages the upper end of stem 37 to unseat the valve and actuating Y roeitheemornaaranrnme at rtfi of the well without'cuttingmiheintak'f gastliiioiighmgrihce,Mwithftherresultmthat incoming.gasfniayicontinue .to.discharge the `ojlfromthetubingamtil.substantially alLoil above the level of the orifice has been ejected.

character employed in combination with the gas pressure lift, knowing the well pressures, it is possible to compute with great accuracy the time through which the well must operate to provide an ultimate delivery of the re- Y quired barrelage. if it is found that the size of one or both fluid inlets must be changed, a combined pulling tool and jar, preferably of the type shown in my prior application, filed November 24, 1931, Serial No. 577,087, for Safety pulling tool for well equipment.l is lowered into the well and engaged with the upper end of the choke which is adapted at 44 for such engagement. By jarring down wardly upon the choke, the frangible pins 2T are broken permitting sleeve 26 to move upwardly with respect to the choke. Vhen the lower en d of sleeve 26 is above the shoulders 30 of the blades, the upper ends of thc blades are forced inwardly so that they will pass the shoulder 20, the springs 28 being at v and sleeve 26 restored to its )ro er osition a'l'ter which the assemblage can be re-run in the well.

The structure shown in Fig. 8, is identical with that previously described with the eX- l ception of the fact that the bean 35 and associated parts, as shown in Figs. l to 7, is substituted for by a downwardly movable bean 45 normally held in engagement with a valve seat i6 formed on the lower end of the choke by a light spring 47, the weight of which is just suflicient to hold the bean against its seat. While a structure of this character does not incorporate the advantage of ability to terminate iiow of oil at a desired point, it incorporates in the choke structure those adber removable through the tubing and mounting said orifices.

4. In oil well apparatus ot' the type described, the combination of a tubing having a gas inlet at a point below the normal level of oil in the well, an oil inlet orifice in said tubing adjacent said gas inlet, said gas inlet and oil inlet orice simultaneously admitting` oil and gas to the tubing and means to close the oil inlet orifice while leaving the gas inlet open.

5. In oil well apparatus of the type described, the combination of a tubing having a gas inlet at a point below the normal level of oil in the well, an oil inlet oriice in said tubing adjacent said gas inlet, said gas inlet and oil inlet orifice simultaneously admitting oil and gas to the tubing means to close the oil inlet orifice while leaving the gas inlet open, and a member removable vantages obtained by the use of downwardly through the tubing and mounting said orifice. releasing bean as set forth in my copending 6, The method of o gratin@ oil Wells comapplication, Serial No. 627,47 9, led August prising simultaneoulladmitting oil and gas Ll, 1932, for Removable choke. i im to the lower end of thetubing wlriiepleter- While I have above consistently referred to F ing the oil, cutting oit' the admission otwil the gas in the Well, it Will be understood that after a, predetermined amount thereof has in many wells the gas pressure provided is been admitted to the tubing, ogitiiluiiig the 'not sufiicient for causing How and under these admission of gas until the oil is discharged circumstances it is the common practice to from the tubing, r Y the well while stili inject in the upper end of the casing air under pponentinggtheuadmigsion of oil to t 1e .u ing pressure for this purpose. Tlierefore,in con and-thenaresumimwminmtwwdl by sideration of the appended claims, the term reducing the gas pressure in the tubing and gas will be understood as including any Lwwrthe tdmissioiiof oil to the tubing. fluid under natural or artificial pressure 7 The method of operating oil wells comwhihdmay be employed in the manner deprising simultaneously admitting oil and gas scri e Since the structure hereinbefore set forth is ing the oil and gas admitted to the tubing, capable of considerable modification without cutting off' the admission of oil after a prein any manner departing` from the Spirit of determined amount thereof has been adniy invention, I do not wish to be understood mitted to the tubing, continuing thev admisas limiting lnySelf thereto eXCept 21S hererlsion of gas until the oil is discharged from the after claimed. tubing, mstingithiiyeli while still prevent- I claimt ing the admission of oil to the tubing and l. In oil well apparatus of the type dethen resuming operation of the well by rescribed, the combination of a tubing having ducing the gas pressure in the tubing and gas and oil .inlets in the lower portion thereresuming the admission of oil to the tubing. of simultaneously admitting oil and gas to 8. The combination in an oil well of a tubthe tubing, and means for closing the oil ing having a gas inlet and an oil inlet, a inlet while leaving the gas inlet open. bored member removably mounted in the 2. In Oil Well applrltUS of the typo Cltubing having` a gas inlet orifice and an oil scribed, the Combination of a tubing llilVIlg inlet orifice communicating with the gas and gas and oil inlets in the lower portion thereoil inlets of the tubing respectively, and sealof simultaneously admitting oil and gas ing means on the member preventing pasto the tubing, orifices controlling said gas sage of iiuids exteriorly ofthe member from and oil inlets, and means for closing the one to the other of said orifices. orifice controlling the oil inlet while leav- 9. The combination in an oil well of a tubing the orice controlling the gas inlet open. ing having a gas inlet and an oil inlet, a 3. In--oil well apparatus of-the-ty-pe-de--boredmemberremovably' -mounted in the scribed, the combination of a tubing having tubing having a gas inlet orifice and an oil gas and oil inlets inv the lower portion thereinlet orifice communicating with the gas and of simultaneously admitting oil and gas to oil inlets of the tubing respectively7 and sealthe tubing, orifices controlling said gas and ing means on the member preventing passage oil inlets, means for closing the orifice conof fluids exteriorly of the member from one to the lower end of the tubi-ng while metertrolling the oil inlet while leaving the orifice to the other ot said orifices or from either controlling the gas inlet open, and a memorifice to the tubing above the member.

10. The combination in an oil well of a tubing having a gas inlet and an oil inlet, a bored member removably mounted in the tubing having a gas inlet orifice and an oil inlet orifice communicating with the gas and oil inlets of the tubing respectively, sealing means on the member preventing passage of fluids exteriorly of the member from one to the other of said orifices, and means to seal the oil inlet orifice while leaving the gas inlet orice open.

11. The combination in an oil well of a tubing having a gas in let,an d anoil inlet, a bored member removably mounted in the tubing having a gasuinlet Q ljvfce. and an oil inlet orifice communicating with the gas and oil inlets of the tubing respectively, sealing means on the member preventing passage of fluids exteriorly of the member from one to the other of said orifices or from either orifice to the tubing above the member, and means to seal the oil inlet orifice whilellea'ving the gas inlet orifice open.

12. In an oil well apparatus of the type described, and in combination, a tubing nipple having an area of increased diameter affording upwardly and downwardly-facing shoul- 'ders, a choke insertable in saidtubing including a plurality of locking blades, springs acting upon the locking blades intermediate the ends thereof to urge them outwardly, a collar embracing the lower ends of the blades to prevent expansion thereof whereby said springs act to urge the upper ends of the blades outwardly to cause said blades to engage beneath the downwardly facing shoulder of the nipple when the choke is inserted therein, and means maintaining the collar in position upon the choke, said means being displaceable upon the application of downward pressure to the choke with the collar in engagement with the upwardlyfacing shoulder whereby said collar may be transferred from the lower to the upper ends of said blades and thereby lock said blades against engagement with the downwardlyfacing shoulder to permit withdrawal of the choke.

13. In oil well apparatus of the type described, the combination of a tubing nipple having upwardly and downwardly-facing shoulders, of a choke insertable in said tubing nipple and having a plurality of locking blades, means acting intermediate the ends of the blades for urging the blades outwardly, a collar to embrace said blades at either end thereof whereby to confine the embraced ends and prevent their engagement with obstructions, and yieldable means normally maintaining said collar in a position upon the choke where it embraces the lower ends of the blades.

14. in oil well apparatus of the type described, the combination of a tubing nipple having upwardly and downwardly-facing shouders` of a choke insertabe in said tubing nipple and having a plurality of locking blades, means acting intermediate the ends of the blades for urging the blades outwardly, a collar to embrace said blades at either end thereof whereby to confine the embraced ends and prevent their engagement with obstructions, yieldable means normally maintaining said collar in a position upon the choke where it embraces the lower ends of the blades, and means upon the blades engaging the collar to prevent downward movement of the collar upon the blades when the collar is positioned to embrace the upper ends of the blades.

15. In apparatus for controlling flow through the tubing of oil wells, a choke in said tubing and having an apertured oil admission bean, the aperture of which is formed at one end with a valve seat. a vertically movable vaive to co-act with said seat, a weight lin said tubing above said choke,fmeans"at the uppernjend of 'the tubing forY supporting and vertically'i'moving the weight, vertical movement of the weight seating and unseating the valve, and means to admit gas to the choke comprising an orifice in said choke above said bean.

16. In apparatus for controlling flow through the tubing of oil wells, a choke in said tubing and having an apertured oil admission bean, the aperture of which is formed at one end with a valve seat, a vertically movable valve to co-act with said seat, a weight in said tubing above said choke, means at the upper end of the tubing for supporting and vertically moving the weight, vertical movement of the weight seating and unscating the valve, and means to admit gas to the choke comprising an orifice in said choke above said bean, the choke having sealing means engaging the tubing above and below said orifice.

' HERBERT C. CTIS. 

